//
// Created by francklinson on 2021/10/21 AT 10:43.
//
#include <iostream>
#include <vector>
#include <unordered_map>
#include <unordered_set>
#include <queue>
#include <algorithm>
#include <functional>
#include <climits>
#include <string>

using namespace std;
class Solution {
public:
    vector<int> getConcatenation(vector<int>& nums) {
        vector<int>ans = nums;
        ans.insert(ans.end(),nums.begin(),nums.end());
        return ans;
    }
};
int main() {
    vector<int>nums{1,2,1};
    Solution solution;
    vector<int>ret  = solution.getConcatenation(nums);
    for(auto &x:ret) cout << x <<endl;
    return 0;
}

